SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e2fc1c226377f1a73bbe71eec0ac6d75270608f6cf9b8138c59754b4c7b2982' 
  AND token = '15rIj0O3fyp/SVVUmY/yrajQILBN/+oP0dVqzhpK6EQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}